People spend a considerable amount of time in a sitting position, such as, sitting at work and at home, and during travel. Typically, the chairs in which the person sits are not ergonomically optimized for the person.
Several patents relating to chairs and seats include:
U.S. Pat. No. 4,765,685, to Kvalheim et al., which discloses a multi-purpose chair with a retractable knee rest. The chair of '685 comprises a typical office chair with attachments and adjustments to provide a knee rest normally positioned beneath the seat cushion.
U.S. Pat. No. 4,650,249 to Serber, discloses an ergonomic seating assembly system with front chest support, pelvic tilt seat component and various attachments to the assembly.
U.S. Pat. No. 4,678,229 to Ryan, discloses a chair, infinitely or incrementally adjustable between an upright seating mode and a full-recline mode, includes a concave seating portion continuous with a convex doubly-extensible leg support portion which combine to form an ergonomically preferred seating attitude when the chair is in a full recline mode.
U.S. Pat. No. 5,857,739 and U.S. Pat. No. 6,022,071 to Smith, disclose a swivel type chair, that functions as both a high back desk chair and a recliner. The seat and backrest pivot as a unit between upright and reclined positions and a footrest is movable pivotally with respect to the seat and is tucked underneath the seat when the chair is in the upright position to function as a desk chair and elevates to an extended position automatically when the chair is moved to the reclined position.
U.S. Pat. No. 6,578,915, to Jonas et al., discloses and adjustable chair and method of use.
US published Patent Application 2005/0179291 to Brodeur, discloses an adjustable cross-legged Yoga position support chair. The chair may include a seat for supporting a user and two adjustable leg supports for supporting the user's left and right thighs at a desired angle when the user sits in a cross-legged position. The seat may also have an attached back support. In another embodiment the chair includes a seat having a surface area wide enough to allow a user to sit on the seat in a cross-legged position and having a tapered front to allow a user's legs to hang comfortably over the front of seat while the user sits in a conventional manner; and a base operatively connected to the seat for supporting the seat, the base for allowing use of the seating chair in a conventional chair-height environment